Varicella (Chickenpox) Vaccine – Live Attenuated (Varilrix, Varivax, ProQuad)

The Varicella (chickenpox) vaccine protects against infection from the varicella-zoster virus. It contains a weakened (live attenuated) form of the virus, which stimulates long-term immunity without causing the full disease. This vaccine helps prevent chickenpox and its complications, such as skin infections, pneumonia, and encephalitis.

Key Features:

Type: Live attenuated vaccine (Oka strain)

Active agent: Weakened varicella-zoster virus

Brands available: Varivax (single-antigen), Varilrix, ProQuad (MMRV combination)

Indications: Prevention of chickenpox in children and adults

Route of administration: Subcutaneous injection (upper arm or thigh)

Contraindications: Immunocompromised individuals, patients on immunosuppressive therapy, pregnant women

Prescription status: Prescription Only Medicine

Storage: Refrigerate at 2°C to 8°C; do not freeze; protect from light

Packaging: Supplied as single-dose vials or pre-filled syringes

Detailed Description:

The Varicella vaccine works by introducing a live, weakened form of the varicella-zoster virus (Oka strain) into the body. The immune system recognizes the virus and responds by creating protective antibodies and memory immune cells. These defenses protect against future infections.

It is routinely used to:

Prevent chickenpox in children (usually at 12–15 months and a booster at 4–6 years)

Protect adults who have not had chickenpox or the vaccine before

Reduce the risk of complications such as bacterial skin infections, pneumonia, or severe illness

Possible Side Effects:

Common: Redness, soreness, or swelling at the injection site; mild fever; mild rash

Less common: Swollen glands, irritability, tiredness

Serious (rare): Severe allergic reaction, seizures, pneumonia, or encephalitis (very rare in healthy individuals)

Storage & Handling:

Store in a refrigerator at 2°C to 8°C

Do not freeze

Keep in original packaging to protect from light

Keep out of reach of children

Disclaimer:

This vaccine must be administered under the supervision of a licensed healthcare professional. Not recommended for individuals with weakened immune systems, pregnant women, or those allergic to any vaccine components. Always consult your doctor before vaccination.